Firstly, familiars are not physical ceeatures. The word 'familiar' in this instance is shortened 'familiar spirit.'

Whether someone's familiar is called, created, or comes on its own; is an ancestor, animal spirit, an aspect of self; whether it remains, comes and goes, or is bound from leaving; and many other aspects, are all a matter of belief.

Some people believe some very different things besides the above.

I suggest doing research into whatever your tradition is and go from there.

if that was possible i wouldn't be chasing my cat around the apartment with a bottle full of coins *see's cat digging in plant* WHAT DID I SAY! *runs after cat shaking bottle*

no, you cannot control animals, you can train animals but you can just look at them, think 'come here' and they obey as if in a trance. it would take a lot of time, patience and effort to train an animal to listen to you. regarding animals on the street, not sure what you mean, but you can show them kindness, people who feed animals will gain some friends. crows have been known to remember people who were nice/mean to them. rewarding those who were nice and attacking those who weren't [my grandmother feeds the crows, i've fed them sometimes too, they can be really nice. one brought me a hair clip once]

regarding familiars, that's a subject up for debate as it's been mystisized so fact and fiction has been tangled together. historically it was believed a witch could either transform into an animal, or tell an animal to do her evil bidding. today many believe a familiar is an animal with whom you have a special bond. others see familiars as some type of spiritual being you can call on for assistance. personally i believe it's a bond between human and animal, but i also believe you can train a pet to assist you in circle. it does depend because animals have personalities, so don't try training your psychotic cat who should be on 'My Cat From Hell' to sit quietly while you meditate in circle. if you have a pet that already enjoys lazing around, you can train them better. but you need to be observant, because sometimes they don't want to sit, they're hungry, or want a walk, or whatever. you need to observe and understand the animals behaviour. you might also consider treating your cat in a similar regard as yourself. many witches try to eat right and exercise to keep healthy, so should you feed your familiar cheap food brands that may be making them sick? or should you research and figure out the best diet for your specific animal? we can't all make our pets food form scratch every week, but perhaps you could look into it and see if you can? or figure out how much exercise your pet needs in a day. maybe your pet is bored, or lonely, keep an eye out and observe to keep your pet happy and healthy.